custom paper size problem

[Sukh]

Hi,
I am tring to change the paper size from default to custom paper size.
In print preview its showing my custom size but when I print it print
on default paper size.
Can any one help me to figure out this?
I am using following code:
Dim customPaperSize As New PaperSize("11x9", 1100, 900)

pdMain.DefaultPageSettings.PaperSize = customPaperSize

'pdmain is Friend WithEvents pdMain As
System.Drawing.Printing.PrintDocument

Thanks in advance
Sukh